Articulated balance for aircraft controls



June 3, 1947. w. s. DIEHL 2,421,374

` ARTICULATED BALANCE FOR AIRCRAFT CONTROLS Filed July 27, 1942 :s sheets-sheet 1 INVENTQ 25 El@ 5 WALTERSD/ L June 3, 1947. w. s. DlEHl. 2,421,374

ARTICULATED BALANCE FOR `IRCRAFT CONTROLS Filed July 27, 1942l 5 sheets-Sheet 2 7 l BY June 3, 1947. w, s, DIEHL 2,421,374

y ARTICULATED BALANCE FOR AIRCRAFT CONTROLS Filed July 27, 1942 3 Sheets-Sheet 3 53M v .52d

` INVENTOR WALTERS. o/EHL Patented June 3, 1947 ARTICULATED BALANCE FOR AIRCRAFT CONTROLS Walter stuart Diehl, United statesiNavy,

Washington, D.. C.

Application July 27, 1942, Serial No. 452,531

(Granted under the act of March, 1883, as amended April `0, 1928; 370 O. G. 757) 6 Claims.

The present invention relates to improvements in aerodynamic balance or control surfaces, particularly to balances shown in United States Patent 2,239,475 to Weick, and in the pending application of Thomas A, Harris Serial No. 427,464.

In aircraft it is `necessary to provide aerodynamic balance for controlling and maneuvering the craft. In order to reduce the hinge moment of control surfaces, and consequently the effort on the part of a pilot to move them, itis common practice to balance the surfaces so that the pilot is relieved of undue exertion. In balancing the control surface, aportion of the surface is placed aheadof the hinge axis, thus providing a means for assisting in the movement of the surface, and utilizing the air pressures on theupper and lower surfaces of the wing or rai-rfoil to balance Ythe moment of a, hinged trailing portion.

An'object of the present invention is the provision of means for preventing the leading edge of a Vcontrol balance from limiting or restricting the available throw.

Another object of -the present invention Vis the provision of an aerodynamic balance that will reduce the hinge moments on aircraft control to a minimum.

A further objectA of the present invention isthe provision of an articulatedI balance positioned ahead of the balanced member.

A still further object of the present Vinvention is the provision of an larticulated balance member that moves substantially parallel to its original position.

A still `further object of thepresentinvention is the provision of means for moving t-he articulated balance in a substantially parallel position.

A still further Vobject of the present invention is the provision of an articulated member that moves substantially parallel to its original position, -thuspreventmg the leading edge of a balance control Vfrom -emerging -beyond lthe boundary of the fixed surface towhich it is attached.

Other objects of the present invention will become `apparent during the course of the following detailed description, taken in connection with the accompanying drawings, forming a part of this specication, and in which drawings:

Figure 1 is'a `fragmentary top plan view 'of av wing and aileron, and illustrating the mounting of the aileron and articulated balance, l

Figure 2 is a diagrammatic transverse vertical section through an aircraft Wing and aileron, and illustrating the-articulated balance and the means connecting thebalance to the aileron, the aileron being shown in its normal, neutral control position, the dotted lines illustrating the positionY of the articulated balance with respect to the position of the'aileron.

Figure 3 is a view'similar to Figure 2 but showing a modified form of means connecting the articulated member tothe aileron, the aileron being shown in its normal or neutral position, the wing being shown fragmentarily.

Figure 4 is a viewsimilar to Figure 3 and illustrating the position the articulated balance assumes when the aileron assumes the position illustrated.

`Figure 5 is a :view similar to Figure 4 but illustrating -amodied form of means connecting the articulated balance -to the aileron.

`Figure 6 is a diagrammatic, transverse, vertical section through an aircraft wing and aileron, and illustrating a modiied form of articulatedbalance and lthe means :connecting the balance to the aileron, and .the seal .carried bythe balance, the aileron being shovvnfin its normal or neutral position.

Figure 'l is .a view similar to Figure 6 .and Villustrating the position the articulated balance assumes when the aileron assumes the Yposition illustrated, the win-g and aileron being shown fragmentarily- Figure is a fragmentary `top'plan view `of a wing -andaileron and illustrating anopening in the wing instead `of a vented chamber.

Figure 9' is a diagrammatic transverse vertical sectional view of the construction shown in Figure 18.

Referring to the drawings, the numeral l0 represents tan Vairfoil having abodyportion Il that has the oppositesides l2 4and 1.3 defining a chamber i4.

Mounted in the body of V,the airfoil ll are brackets Isisupporting afshaft lthat carries an aileron .Il provided with an arcuate portion 1 8. At this .point .I A.wish tohave it understood, that, although I have shown a `shaft upon which ,the aileron is mounted, other means may be employed for mounting the aileron. The arcuate `portion t8 receives a `corresponding portion `Il) of ,an articulated memberlil pivotally mounted in any suitable manner-in :the aileron, such @as by bearing pins .2.1. The articulated member 20 is Aprovided with a flexible member 22, the members 20 and 22 dividing Ithe chamber i4 into compartments23 and :2.4, themarginaledge `25 of the vflexible member 2,2 engaging :the wall `Zztiof the chamber t4. The ends 21 and .28 of vthe sides I2 and I3 are spaced 4from :the aileron, .providing vents or lpazs- 3 sages or slots 29 and 30. The bracket |5 and the articulated member 20 have grooved drums 3| and 32 rigidly secured to the respective members, and around the drums there is trained a belt 33.

In Figures 3 and 4, I have illustrated a modified form of my invention, in which the bracket |a is provided with a horn 34 and a rounded nose portion 35. The brackets |5a at 36 support an aileron l'la, the aileron at 31 having an irregular grooved portion 38, providing free movement of the aileron around the nose portion 35.

In the chamber |4a, there is an articulated member 39 provided with an arm 40, and an arcuate portion 4| that engages an arcuate portion 42 that may be a bearing in the leading edge of. the aileron I'Ia. The arm 40 is connected to the horn 34 by a link 43, and there is .provided in the side |2a, slot 44 for free movement of the arm 40. If desired, a fabric seal 45 may be provided between the articulated balance 39 and the portion or bearing 42.

In the form of modification illustrated in Figure 5, the construction is similar to Figure 2 and I have provided, in this modication, sprocket wheels 448 and 49 that are mounted on shafts or pin bearings |6b and 2lb, the sprockets being rigidly xed to the bracket and the articulated balance respectively. The sprockets 48 and 49 have trained around them a sprocket chain 50.

In the modification as illustrated in Figures 6 and 7, the aileron 5| is mounted on a shaft |8c, the aileron being provided with an arcuate portion |8c. Fixedly secured to the aileron shaft |6c is a member 52 having a finger 53. The arcuate portion IBc receives a corresponding portion 54 of an articulated member 55 that is pivotally mounted on bearing pins 2Ic. The member 55 has an arm 56 that is connected to the finger 53 by a link 51. It is to be noted that the side |2c of the body portion ||c of the airfoil |00 is provided with a slot 58. In the member 55, as illustrated in dotted lines 59, I have shown a plunger type of seal instead of the flexible type as shown in the other views. In this type of seal the plunger at one end engages a spring 60, the opposite end engaging the wall 26o.

The modification illustrated in Figures 8 and 9 differs from the structure illustrated in Figures 6 and 7 in that the wing ||d is provided with an opening 6| instead of a vented chamber, andthe articulated member 55d is provided with a flexible flap 22d.

In the operation of the device, as illustrated in Figures 1 and 2, the drum 3|, being lxedly secured to the bracket |5 and the drum 32 fixed to the articulated member 20, movement of the aileron in the direction indicated by dotted lines A will impart motion to the articulated member 20 through the medium of the belt 33, the articulated member assuming the position as indicated by the letter B. During the movement of the aileron and the articulated member, the articulated member will move in a parallel motion to its original position, the flexible member or seal 22 assuming the .position as shown by the dotted line. Upward movement of the aileron as indicated by the letter C will move the articulated member to a position indicated by the letter D.

The loperation of the modification as illustrated in Figures 3 and 4 is the same as illustrated in Figures 1 and 2 except that movement of the articulated member is effected by the arcuate portion 4| engaging bearing 42 and the link 43 4 connecting the articulated arm 40 to the horn 34 of the bracket |5a.

The operation of the modification illustrated in Figure 5 is the same as shown in Figure 2, the difference being the use of sprockets and chain drive instead of drums and a belt.

In the modification, as illustrated in Figures 6 and 7, the articulated member simulates a bell crank and it is provided with a plunger type of seal.

The operation of the modification as illustrated in Figures 8 and 9 is the same as illustrated in Figures 6 and '7.

Various changes may be made in the forms of invention herein shown and. described without departing from the spirit of the invention or the scope of the following claims.

The invention described may be manufactured and/0r used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What I claim is:

1. In a control surface for aircraft, a fixed surface and a movable control surface, a recess in the fixed surface, an articulated extension on the leading edge of said movable surface, means for vertically moving said articulated extension in said recess in a substantially horizontal position, a flexible flap carried by said articulated member, said flexible flap being secured to a wall in said recess and to the forward edge of said articulated extension and dividing said recess into upper and lower compartments, said compartments being vented to the atmosphere on their respective sides.

2. In a control surface for aircraft, a fixed surface and a movable control surface, a recess in the fixed surface, an articulated extension on the leading edge of said movable control surface, means for vertically moving said articulated extension in said recess in a substantially horizontal position, a flexible flap carried by said articulated member and so secured whereby said recess is divided into separate compartments which are thereby sealed from each other, said compartments being vented to the atmosphere on opposite sides of said dividing fiap and articulated member. V

3. In a control surface for aircraft, a fixed surface and a hinged control surface, a recess in said fixed surface forward of said hinged surface, vent means for said recess, an articulated extension on the leading edge of said hinged control surface, a flexible flap carried by said articulated member, said extension, -control surface and flap dividing said recess into two sub recesses sealed from each other and means for vertically moving said articulated extension in said recess in a substantially horizontal position.

4. In a control surface for aircraft, a fixed surface and a hinged control surface, a recess in said fixed surface forward, of said hinged surface, vents in said recess, an articulated extension on the leading edge of said hinged surface housed in said recess, a flexible flap carried by said articulated member, and means for vertically moving said articulated extension in said recess in a substantially horizontal position. f

5. In a control surface for aircraft, axed surface and a hinged control surface, a recess in said xed surface forward of said hinged surface, vents in said recess, an articulated'extension on the leading edge of said Vhinged control surfacezhoused insaid recess, a sealY in said recess, one end of said seal being in engagement with a wall of said recess, the opposite end of said seal being in engagement with the leading edge of said articulated member, and means for vertically moving said articulated extension in said recess in a substantially horizontal position, said seal and articulated member dividing said recess into two compartments sealed from each other, said vents in each said compartment, admitting differential pressures into said compartments.

6. In a control surface for aircraft, a xed surface and a. hinged control surface, a recess in said xed surface forward of said hinged control surface, vents in said recess, an articulated extension on the leading edge of said hinged control surface and housed in said recess, a seal in said recess, one end of said seal :"Deing in engagement with a wall of said recess, the opposite end of said seal being in engagement With the leading edge of said articulated member, means for vertically moving said articulated extension in said recess in a substantially horizontal position, said articulated member and seal dividing said recess into compartments sealed from each other, said vents ineach said compartment admitting differential pressures into said compartments.

WALTER STUART DIEHL.

REFERENCES CITED The 'following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,222,187 Weatherbee Nov. 19, 1940 1,574,567 Flettner Feb. 23, 1926 2,211,870 Wagner et al Aug. 20, 1940 2,239,475 Weick Apr. 22, 1941 2,252,284 Child Aug 12, 1941 2,281,696 Johnson May 5, 1942 2,361,275 Davie Oct. 24, 1944 FOREIGN PATENTS o Number Country Date 441,603 France May 30, 1912 546,815 France Sept. 4, 1922 642,042 Germany Feb. 20, 1937 693,900 Germany July 20, 1940 

